Study finds a very neat intersection of physics and biology.

It may come as a shock to learn that 50 billion of your body’s cells met their end yesterday, at their own hand no less. It would, however, be wise to get used to it because it will happen today and again tomorrow. It is called apoptosis and is, in fact, essential for survival.

Each day the body produces billions of excess cells that are slated for removal. In early life, some of that is just healthy embryology, such as the creation of fingers in the foetus by the carving of web spaces in its paddle-shaped hands – think of a sculptor building a clay model only to cleave away the surplus to reveal an exquisite Renaissance rendering of David.

But apoptosis also keeps aberrant growth at bay, for example, by pruning back misdirected neurons or imploding immune cells that wrongly turn on the self. It is a delicate balance. Too little apoptosis and cells would become cancerous, too much and the organ withers.

Our understanding of how the process occurs just got a boost from a study by Xianrui Cheng and James Ferrell at the Stanford University School of Medicine, California, US.

The researchers were faced with two candidate mechanisms for how death propagates through cells.

Read the full article in Cosmos magazine here